For testing purposes and for analog processing of signals, it is desirable to generate an analog sine signal that can be regulated as to the signal's frequency and phase. One technique used to generate a sine signal is to store a sine function in a table in a memory. The table contains digital values that, when converted to an analog signal using a digital to analog converter (DAC), generate the analog sine signal. This technique may require a large number of transistors to construct the DAC and thus uses an unnecessarily large amount of semiconductor layout space. Further the resolution of the sine value is often portrayed inaccurately.
Rectangular shaped resistive strips connected to a switch with a common output have been used to generate sine waves. These rectangular shaped resistive strips have a voltage applied across opposing edges of the strip, and legs are placed at interval locations. Switches are connected to the legs and are selected to pass the voltage levels on the legs to a common output. This conventional rectangular-shaped strip undesirably consumes a relatively large amount of silicon in the semiconductor device. Further, the precise spacing of the legs needed to obtain an appropriate sine function is not always exact or sufficiently accurate and repeatable in production, resulting in strips that generate imprecise sine waves at the output.